Surface coverings, notably floor, wall and ceiling coverings, or desk, table and counter tops, or the like, have been made for many years and presently normally comprise one or more layers of the same or different resinous polymeric compositions, usually polyvinyl chloride homopolymers or copolymers, or polyurethane resins, or the like, and a relatively dimensionally stable fibrous backing material therefor, normally comprising a felted or matted fibrous sheet of asbestos or cellulosic fibers which may be impregnated with water-resisting and/or strengthening materials.
Such a surface covering must be dimensionally stable under various atmospheric conditions and under varying moisture situations. For example, if such a surface covering was intended to be cemented to a floor or other substrate by means of a water-soluble paste or adhesive and the fibrous backing material was susceptible to various dimensional changes upon exposure to moisture-or water-containing materials, it would change dimensions and would normally expand upon being contacted by the water-soluble paste or adhesive, or upon exposure to varying moisture conditions and situations. However, on the other hand, the resinous polymeric compositions on top of the fibrous backing materials would either not expand at all or else would change dimensions to a different degree, whereby the surface covering would undesirably buckle or curl upwardly, particularly where adjacent pieces of the surface covering were fitted or joined together.
It is additionally also important that such fibrous backing materials also be dimensionally stable under varying temperature conditions and situations, particularly during further manufacturing processing and finishing of the surface covering under elevated conditions of temperature.